Container



July 30, 1963 G. o. SCZHROEDER CONTAINER Filed Jan. 18, 1961 m 0 NZ m5 N m 5 J a f 6 BY %M@M Patented July 30., 1963 3,099,378 CONTAINER George Oscar Schroeder, Palatine, 111., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed Jan. 18, 1961, Ser. No. 83,426 13 Claims. (Cl. 229-5.5)

The present invention relates to a fiber container having a protective lining suitable for the packaging and delivery of milk, fruit juices, or similar liquid products and has particular reference to an improved liquid-proof lap scam in such a container.

In containers made from coated fiber sheet materials, lap type seams are widely employed because of their strength, simplicity of construction and ease of fabrication. A disadvantage of the conventional lap seams used is that the marginal cut edge of the inner ply of the seam has a fiber portion which is exposed to liquid products placed within the container. Due to a wicking action, the liquids tend to penetrate and soak into the unprotected fiber weakening the fiber and often leading to a failure of the seam.

In the past, the raw fiber edge has been protected against wicking by the application of a coating of wax or like material to the fiber edge either before or after the seam is formed. However, in the formation of such a container, portions of the edge may be severely bent so as to result in a fracture of a pre-applied protective coating. Also, such containers are often subjected to rough treatment during filling and transportation to the ultimate consumer which may cause a fracture in the somewhat brittle wax coating thereby giving the liquid contents access to the fiber stock. The liquid seepage into the fiber stock though localized, softens the fiber so that a leak of varying proportions may eventually develop in the container seam.

The present invention contemplates overcoming this undesirable condition by providing a container made from fiber sheet material having a liquid impervious coating or layer on one surface thereof and having lap seams joining the respective parts in which the inner liquid impervious coating or layer is extended around the marginal edges of the inner plies to terminate within the bonded portion of the scam. in this manner, the interior of the container is completely covered by the liquid impervious coating and no exposed fiber is presented to the liquid contents.

Accordingly, an object of the present invention is the provision of a fiber container having an inner liquid impervious layer which layer completely covers the interior surfaces of the container.

Another object is to provide such a container having a lap seam in which the raw fiber edge of the inner ply is protected by the liquid impervious layer from the deteriorating effects of liquids which :are placed within the container.

Another object is to provide such *a container having a lap seam whose thickness is substantially the same throughout.

A further object is to provide such a container having a lap seam whose thickness is approximately equal to the combined thicknesses of the material being joined.

Still a further object is to provide such a container which can be easily fabricated.

Numerous other objects and advantages of the inven tion will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

FIGURE 1 is a perspective view of a container embodying the instant invention;

FIGURES 2 and 3 "are enlarged fragmentary sectional views taken substantially along the planes indicated by the lines 2-2 and 33 respectively in FIG. 1;

FIG. 4 is a view similar to FIG. 2 showing a modified form of the invention.

As a preferred or exemplary embodiment of the instant invention, the drawings illustrate a container 11 having a body 12 which is substantially square in cross-section and is provided with imperforate end members 13. The body 12 and end members 13 are preferably made of a sheet material consisting of a fiber layer 15 such as paperboard having a liquid impervious layer 16 on one surface thereof with the liquid impervious layer disposed towards the interior of the containers. The liquid impervious layer 16 is preferably a thin plastic film such as polyethylene although it is to be understood that other materials such as metallic foils, liquid proof paper, etc. would also be suitable.

The body 12 is preferably formed from a single sheet of material which is folded at right angles to provide four side walls 17. The edges of the body material are overlapped and joined along one of the side walls 17 in a vertically disposed lap side seam 18. The seam 18 consists of an outer ply 19 and an inner ply 20 having their contiguous surfaces 23 adhesively secured together by suitable rneans to form a liquid tight seam.

The inner ply 20 has a folded edge 24 in which the liquid impervious layer 16 completely encloses the fiber layer 15- (FIG. 2). The folded edge 24 is produced on the sheet material before it is folded into a body 12 preferably by skiving or tapering the fiber layer 15 along a narrow strip adjacent the edge of the material to sub stantially a feather edge 25 formed by the liquid impervious layer 16. The skived strip is then folded back upon itself with the liquid impervious layer 16 disposed outwardly of the fold forming the folded edge 24. The dimensions of the skived strip and the location of the fold are preferably selected so as to result in the folded edge 24 having an overall thickness approximately the same as the thickness of the original material.

In the completed side seam 18, the liquid impervious layer 16 extends around the folded edge 24 with its terminal edge 25 interposed between the bonded plies 1'9 and 20. Thus there is provided a strong lap side seam 18 for the body 12 with the liquid impervious layer 16 completely covering the inner surface of the seam.

T he body 12 is bent obliquely inwardly adjacent each end to effect an inwardly inclined reinforcing truss portion 26 and is then bent outwardly in a relatively sharp corner to form a horizontal outwardly extending flange 27 (FIG. 3). The outwardly extending flange 27 cooperates with the inwardly inclined truss portion 26 to provide a rigid structure which resists outward and inward movement of the body walls 17 adjacent thereto.

The extreme end portions of the body 12 are bent horizontally inwardly in contiguous relation to the horizontally outwardly extending flanges 27 to form inwardly extending flanges 28. The flanges 27 and 28 cooperate to form a rigid supporting ledge 29 on which the end members 13 are seated with the inwardly extending flanges 28 forming the inner plies of lap seams 30 attaching the end members to the body 12. The outer plies 33 of the seams 30 are formed by peripheral margins of the end members 13 which margins are 'adhesively secured by suitable means to the inwardly extending flanges 28.

The flanges 28 have skived and folded edges 34 formed in the same manner as heretofore described for the folded edge 24 of the inner ply 20 of the side seam 18. Thus the liquid impervious layer 16 extends around the folded edge 34 and has its terminal edge 35 interposed and sealed between the two adhesively bonded plies 28 and 33 forming the end seam 30.

It is to be understood thatladhesively bonding together the skived and folded portions composing the folded edges may sometimes be desirable to facilitate the container forming and assembly operations. For example, in the embodiment shown in FIG. 1, subsequent to the formation of the folded edge 34 the adjacent material is subjected to rather severe deformation in the forming of the reinforcing truss portion 26 and flanges 27 and 28. These forming operations tend to unfold in varying degrees port-ions of the folded edges 34. The unfolded edge portions may hinder the proper formation of the end seams 30 and could result in the exposure of raw fiber subject to wicking in the end seams. Consequently, adhesively bonding together the skived and folded portions forming the folded edge 34 will generally be desirable. However, adhesively bonding the skived and folded portions forming the folded edge 24 will generally be unnecessary since in the operation whereby the end seam 18 is formed, the ply 19 may be directed across the ply in a manner which urges the folded edge 24 towards the folded position so that the side seam will be properly formed.

In the modified form of the invention shown in FIG. 4, a container body 36 is provided without the reinforcing structure adjacent its ends. In this form of the invention, the end portions of the body 36- are bent horizontally inwardly to form flanges 37. Each flange 37 is adhesively attached to a peripheral margin 38 of an end member 39 to form a lap end seam 4t) therewith, the flange 37 forming the inner ply of the seam. The flange 37 has a folded edge 41 formed in the same manner as heretofore described so as to fully enclose the raw edge of the fiber layer 15 within the liquid impervious layer 16.

While the foregoing description of the present invention has been confined to a container made from a fiber material having a liquid impervious layer on only one surface thereof, it is to be understood that the invention is equally applicable to containers made from fiber sheet material having liquid impervious layers on both surfaces. It is to be further understood that in such a container made from fiber sheet with protective layers on both surfaces thereof, both the inner and outer plies of the lap seams may have the novel folded edge structure disclosed so that both inner and outer surfaces of the container are free of exposed fiber edges.

It will be readily apparent that the seamed fiber container of the present invention has the very desirable feature in that all of the fiber surfaces including the raw cut edges of the seams are positively protected from contact with the contents of the container. Furthermore, this raw edge protection is effected without the separate application of :a liquid-proof coating such as wax to the fiber edges.

An additional advantage is that containers having the seam structure disclosed can be easily formed using conventional seam forming equipment. The thinning or skiving of the fiber layer facilitates the folding of a narrow margin of the material and reduces the tendency of the folded edge to spring open when the bending force is removed even though the skived and folded portions are not adhesively bonded together. Also, since the folded edge has a thickness approximately the same as the thickness of the original material, the lap seam has substantially a uniform thickness throughout equal to the combined thicknesses of the material being joined. Consequently, the conventional seaming equipment used to form lap seams by adhesive bonding, dielectric heat sealing, etc., can generally be used to form the novel seams of the subject container.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction, and arrangement of the parts Without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. A container formed from a fiber sheet material having a liquid impervious layer on at least one surface thereof comprising a tubular body, a longitudinally extending side seam on said body, an end closure and an end seam securing said end closure to said body, said body and said end closure having said liquid impervious layer disposed interiorly of the container, said seams being lap seams formed by two overlapped margins having contiguous surfaces bonded together, the interiorly disposed margin of at least one of said lap seams having a folded edge comprising a marginal portion having the fiber remote from said liquid impervious layer tapered towards a terminal edge and forming substantially a feather edge at said liquid impervious layer, said tapered marginal portion being folded back upon itself with said liquid impervious layer disposed outwardly of the fold, said folded edge having an overall thickness not exceeding the thickness of the adjacent material, the liquid impervious layer of said interiorly disposed margin extending around said folded edge and having a terminal edge interposed between the bonded surfaces of said lap seam whereby the interior surface of said lap seam is free of exposed fiber surfaces.

2. The container set forth in claim 1 wherein the interiorly disposed margin of said side seam has said folded edge configuration.

3. The container set forth in claim 1 wherein the interiorly disposed margin of said end seam has said folded edge configuration.

4. The container set forth in claim 1 wherein the interiorly disposed margins of said side seam and said end seam have said folded edge configuration.

5. The container set forth in claim 1 having an end closure member secured by an end seam on both ends of said tubular body.

6. The container set forth in claim 5 wherein the interiorly disposed margins of said side seam and said end seams have said folded edge configuration.

7. The container set forth in claim 1 wherein said liquid impervious layer consists essentially of a polymer of an ethylenically unsaturated monomer.

8. The container set forth in claim 1 wherein said liquid impervious layer is a film of polyethylene.

9. The container set forth in claim 1 wherein said tubular body is substantially square in cross section.

10. A liquid-proof container formed from a fiber sheet material having a liquid impervious layer on at least one surface thereof comprising, a tubular body formed with the liquid impervious layer facing interiorly and adhesively sealed along overlapping margins to form a longitudinally extending lap side seam, an inwardly directed flange formed on an end of said body by bending the terminal portion inwardly substantially at right angles to the longitudinal axis of said body, and an end closure disposed outwardly from and adhesively secured adjacent its periphery to said flange to form a lap end seam therewith, said end closure having the liquid impervious layer facing the interior of the container, the inner ply of said side and end lap seams having a skived and folded back marginal edge portion formed by tapering said fiber material towards a terminal edge of said liquid impervious layer to form substantially a feather edge at said liquid impervious layer and folding said tapered edge portion back upon itself with said liquid impervious layer disposed outwardly of the fold, said skived and folded edge portion having an overall thickness not exceeding the thickness of the adjacent material, the liquid impervious layer of said inner ply extending completely around said skived and folded portion and having a terminal edge interposed between the adhesively bonded surfaces of said lap seam whereby the fibre material is free from contact with the contents of the container and protected therefrom by said liquid impervious layer.

11. The container set forth in claim 10 wherein the said inwardly directed flange is formed on both ends of said body and having an end closure member for each end of said body, said end closures having their peripheral margins adhesively secured to said flanges and forming lap end seams therewith.

12. The container set forth in claim 11 wherein at least one end of said body is bent obliquely inwardly to form :a truss portion to brace the body Wall against inward and outward movement, then horizontally outward in a relatively sharp corner, and thence horizontally inward in contiguous relation to the said horizontally out- 6 ward extending portion, said horizontally inward extending portion froming the said inwardly directed flange.

13. The container set forth in claim 12 wherein both ends of said body have the end structure recited in claim 12.

References Cited in the file of this patent UNITED STATES PATENTS 1,617,274 Romer Feb. 8, 1927 1,866,230 Stubbs July 5, 1932 2,056,092 Clafi Sept. 29, 1936 2,328,579 Pelosi Sept. 7, 1943 2,415,323 Wilcox Feb. 4, 1947 FOREIGN PATENTS 1,019,548 Germany Nov. 14, 1957 

1. A CONTAINER FORMED A FIBER SHEET MATERIAL HAVING A LIQUID IMPERVIOUS LAYER ON AT LEAST ONE SURFACE THEREOF COMPRISING A TUBULAR BODY, A LONGITUDINALLY EXTENDING SIDE SEAM ON SAID BODY, AN END CLOSURE AND AN END SEAM SECURING SAID END ENCLOSURE TO SAID BODY, SAID BODY AND SAID END CLOSURE HAVING SAID LIQUID IMPERVIOUS LAYER DISPOSED INTERIORLY OF THE CONTAINER, SAID SEAMS BEING LAP SEAMS FORMED BY TWO OVERLAPPED MARGINS HAVING CONTIGUOUS SURFACES BONDED TOGETHER, THE INTERIORLY DISPOSED MARGIN OF AT LEAST ONE OF SAID LAP SEAMS HAVING A FOLDED EDGE COMPRISING A MARGINAL PORTION HAVING THE FIBER REMOTE FROM SAID LIQUID IMPREVIOUS LAYER TAPERED TOWARDS A TERMINAL EDGE AND FORMING SUBSTANTIALLY A FEATHER EDGE AT SAID LIQUID IMPERVIOUS LAYERS, SAID TAPARED MARGINAL PORTION BEING FOLDED BACK UPON ITSELF WITH SAID LIQUID IMPERVIOUS LAYER DISPOSED OUTWARDLY OF THE FOLD, SAID FOLDED EDGE HAVING AN OVERALL THICKNESS NOT EXCEEDING THE THICKNESS OF THE ADJACENT MATERIAL, THE LIQUID IMPREVIOUS LAYER OF SAID INTERIORLY DISPOSED MARGIN EXTENDING AROUND SAID FOLDED EDGE AND HAVING A TERMINAL EDGE INTERPOSED BETWEEN THE BOUND SURFACES OF SAID LAP SEAM WHEREBY THE INTERIOR SURFACE OF SAID LAP SEAM IS FREE OF EXPOSED FIBER SURFACES. 